SOLUTION: In an exam there is 4 marks for a right answer but 2 marks will be deducted for a wrong answer. A student attends 75 questions and gets 150 marks.How many questions did he answer r
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Question 1049618: In an exam there is 4 marks for a right answer but 2 marks will be deducted for a wrong answer. A student attends 75 questions and gets 150 marks.How many questions did he answer right? Answer by jorel555(1290) (Show Source):
You can put this solution on YOUR website! Let r be right answers, and w be wrong ones. Then:
r+w=75
4r-2w=150;
2r+2w=150
add these together, we get;
6r=300
r=50
w=25
There were 50 right answers, and 25 wrong. ☺☺☺☺
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